Membrane digital analog switches

ABSTRACT

A membrane digital analog switch includes an input button surface adapted to receive an input pressure from a user, and a digital switch positioned below the input button surface to generate a digital switch activation signal when the received pressure on the input button surface is greater than or equal to a specified digital pressure threshold. The membrane digital analog switch also includes an analog switch adapted to generate an analog switch activation signal when the received pressure on the input button surface is greater than or equal to a specified analog pressure threshold. The specified analog pressure threshold is greater than the specified digital pressure threshold, the digital switch activation signal is a binary digital signal, and the analog switch activation signal is variable and corresponds to an analog sensed value of the received pressure on the input button surface.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.16/396,049 filed Apr. 26, 2019 (issuing as U.S. Pat. No. 10,523,233 onDec. 31, 2019). The entire disclosure of the above application isincorporated herein by reference.

FIELD

The present disclosure generally relates to membrane digital analogswitches.

BACKGROUND

This section provides background information related to the presentdisclosure which is not necessarily prior art.

Keypads sometimes include membrane digital switches, such as tactileswitches including metal domes, non-tactile metal switches includingconductive pads, etc. Separately, a force-sensing resistor includes amaterial whose resistance changes when a force, pressure, mechanicalstress, etc., is applied.

DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIG. 1 is a block diagram of a membrane digital analog switch accordingto one example embodiment of the present disclosure;

FIG. 2 is a block diagram of a membrane digital analog switch includinga force-sensing resistor in series with a digital switch according toanother example embodiment of the present disclosure;

FIG. 3 is a top view of a keypad including two membrane digital analogswitches as shown in FIG. 1;

FIG. 4 is a top view of a keypad including two membrane digital analogswitches as shown in FIG. 2;

FIG. 5 is a cross-sectional view of a tactile switch according toanother example embodiment of the present disclosure; and

FIG. 6 is a cross-sectional view of a non-tactile switch according toanother example embodiment of the present disclosure.

Corresponding reference numerals indicate corresponding (but notnecessarily identical) parts throughout the several views of thedrawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference tothe accompanying drawings.

Disclosed herein are exemplary embodiments of membrane digital analogswitches. A membrane digital analog switch may combine digital andanalog switch functions in a single button where an initial press of thebutton generates a digital signal, and further pressure on the buttonadjusts an analog signal value corresponding to the input pressure.

These example membrane digital analog switches may be used in anysuitable applications, such as applications where a positive on step isrequired before analog functionality is engaged, etc. Some exampleapplications include a crane remote control for two speeds, threespeeds, more than three speeds, etc., where the different speedscorrespond to a current analog value of the membrane digital analogswitch.

In some embodiments, a membrane digital analog switch may be used for acrane control where a crane has a stepless drive and input pressure(e.g., from a thumb, finger, etc.) controls a speed of the crane, or amachine control where a flow rate is proportional to input pressure(e.g., a concrete pump, a pressure washer, etc.). As another example,vehicle speed could be controlled according to input pressure (e.g., fora tracked vehicle, etc.).

The digital switch may include any suitable digital switch elementcapable of generating a digital activation signal (e.g., a binary on oroff signal, etc.) in response to a user applying input pressure above adigital pressure threshold. For example, the digital switch may includea mechanical digital switch such as a cap switch, a rocker switch, atactile switch (e.g., including a metal dome), a non-tactile switch(e.g., including an electrically-conductive pad), etc.

As the user increases pressure at or above the digital switch activationthreshold, the analog switch element may output, sense, detect, etc., ananalog signal switch activation signal that changes in response tochanges in the input pressure. For example, the analog switch mayinclude a force-sensing resistor whose resistance changes when a force,pressure, mechanical stress, etc. is applied. The changing resistancemay be measured and used to control a speed or other suitable functionof a crane, machine, vehicle, etc., according to the input pressure fromthe user.

In a rocker switch, an initial pressure could activate the digitalswitch, while further pressure in the same motion adjusts analogfunctionality of the analog switch. Similarly, a tactile switch mayallow for initial digital signal activation followed by analog controlin a same motion of applying pressure to the top of the tactile switch.

In some embodiments, the force-sensing resistor may have a non-linearcharacteristic, may have low repeatability, etc. The force-sensingresistor may have an initial high resistance and fall rapidly aspressure is initially increased, then change resistance more slowly asthe pressure continues to increase. Accordingly, the force-sensingresistor of the analog switch element may be combined with the digitalswitch element in different optional arrangements.

For example, the analog force-sensing resistor may be connected inseries with a second digital switch, so the starting point of userengagement of the analog switch force-sensing resistor is clear. Whenthe digital switch closes, an initial resistance may be measured and theremaining resistance slope of the force-sensing resistor may becalibrated from the measured initial resistance.

As another example, a force-sensing resistor may be used directly forthe analog switch (e.g., placed below the digital switch, etc.), and theresistance value of the force-sensing resistor may be measuredsubstantially continuously. As the first digital switch closes the slopeof the force-sensing resistor changes, and a controller, firmware, etc.,may interpret the changing slope of resistance to determine a level ofanalog switch activation.

Combining a digital switch element and an analog switch element into amembrane design may reduce a cost of a keypad, reduce a complexity ofthe keypad, increase reliability, allow for a more compact physicalpackage that takes up less space, etc. The keypad may have signal linesthat are buried within power planes for greater electromagneticimmunity.

In some embodiments, membrane digital analog switches may include a SafeDesign process to facilitate (e.g., ensure) Performance Level D byutilizing dual channel and time domain architecture. For example,redundancy may be used to reduce the likelihood of (e.g., prevent) afault that takes down both channels, by taking measurements of first andsecond stages at different times (e.g., sequentially) and determiningthat the other stage is not currently activated.

In an example embodiment, a membrane digital analog switch includes aninput button surface adapted to receive an input pressure from a user,and a digital switch positioned below the input button surface togenerate a digital switch activation signal when the received pressureon the input button surface is greater than or equal to a specifieddigital pressure threshold.

The membrane digital analog switch also includes an analog switchadapted to generate an analog switch activation signal when the receivedpressure on the input button surface is greater than or equal to aspecified analog pressure threshold. The specified analog pressurethreshold is greater than the specified digital pressure threshold, thedigital switch activation signal is a binary digital signal, and theanalog switch activation signal is variable and corresponds to an analogsensed value of the received pressure on the input button surface.

The analog switch may include a force-sensing resistor, and theforce-sensing resistor may have a non-linear resistance characteristicwhere a resistance of the force-sensing resistor decreases non-linearlyas pressure on the input button surface is increased. The membranedigital analog switch may include a controller configured to measure theanalog switch activation signal, and to determine the received inputpressure on the input button surface according to the measured analogswitch activation signal.

For example, the controller may be configured to determine a change inslope of the analog switch activation signal, and compare the change inslope to the non-linear resistance characteristic of the force-sensingresistor to determine the received input pressure on the input buttonsurface.

In some embodiments, the analog switch including the force-sensingresistor is positioned below the digital switch with respect to theinput button surface. The digital switch may be a first digital switch,and the membrane digital analog switch may further include a seconddigital switch positioned below the first digital switch with respect tothe input button surface. The analog switch including the force-sensingresistor may be coupled in series with the second digital switch.

The controller may be configured to detect a second digital switchactivation signal when the second digital switch is closed, and measurean initial resistance of the force-sensing resistor in response todetecting the second digital switch activation signal. The controllermay set the measured initial resistance as a calibration value formeasuring an analog force-sensing resistor signal corresponding to theresistance of the force-sensing resistor to determine the received inputpressure on the input button surface.

In some embodiments, the input button surface and the digital switchdefine a tactile switch including a metal dome, and the input buttonsurface includes an overlay contacting a first side of the metal dome. Asecond side of the metal dome opposite the first side is positioned tocontact an electrical conductor of the digital switch in response to thereceived pressure on the overlay contacting the first side of the metaldome.

Alternatively, the input button surface and the digital switch maydefine a non-tactile switch including an electrically-conductive pad,where the input button surface includes an overlay contacting a firstside of the electrically-conductive pad. A second side of theelectrically-conductive pad opposite the first side is positioned tocontact an electrical conductor of the digital switch in response to thereceived pressure on the overlay contacting the first side of theelectrically-conductive pad.

The controller may be configured to determine a positive on step inresponse to receiving the digital switch activation signal, and inresponse to determining the positive on step, to implement one or moreanalog functions according to the received analog switch activationsignal. For example, the one or more analog functions may includecontrolling a speed or flow rate of a machine, controlling the speed ofa crane or a vehicle, controlling the flow rate of a concrete pump or apressure washer, etc.

With reference to the figures, FIG. 1 illustrates an example membranedigital analog switch 100 according to some aspects of the presentdisclosure. The membrane digital analog switch 100 includes an inputbutton surface 102 adapted to receive an input pressure from a user, anda digital switch 104 positioned below the input button surface 102 togenerate a digital switch activation signal when the received pressureon the input button surface 102 is greater than or equal to a specifieddigital pressure threshold.

The membrane digital analog switch 100 also includes an analog switch106 adapted to generate an analog switch activation signal when thereceived pressure on the input button surface 102 is greater than orequal to a specified analog pressure threshold. The specified analogpressure threshold is greater than the specified digital pressurethreshold. The digital switch activation signal is a binary digitalsignal, and the analog switch activation signal is variable andcorresponds to an analog sensed value of the received pressure on theinput button surface 102.

The analog switch 106 includes a force-sensing resistor (FSR) 108. Theforce-sensing resistor 108 may have a non-linear resistancecharacteristic where a resistance of the force-sensing resistor 108decreases non-linearly as pressure on the input button surface isincreased.

For example, the force-sensing resistor 108 may include anelectrically-conductive polymer, which changes resistance in apredictable manner following application of force to its surface. Theforce-sensing resistor 108 may include a polymer sheet or ink that canbe applied by screen printing.

The sensing film may include both electrically conducting andnon-conducting particles suspended in a matrix, and the particles mayhave sub-micrometre sizes. Applying a force to the surface of thesensing film causes the particles to touch the electrically conductingelectrodes, which changes a resistance of the film. FSRs may have athickness of less than 0.5 mm, etc., low cost, good shock resistance,etc. However, some FSRs may have low precision (e.g., measurements thatmay differ by 10% or more, etc.).

As shown in FIG. 1, the membrane digital analog switch 100 may includean optional controller 110 configured to measure the analog switchactivation signal, and to determine the received input pressure on theinput button surface according to the measured analog switch activationsignal.

For example, the controller 110 may be configured to determine a changein slope of the analog switch activation signal, and compare the changein slope to the non-linear resistance characteristic of theforce-sensing resistor to determine the received input pressure on theinput button surface 102.

As shown in FIG. 1, the analog switch 106 including the force-sensingresistor 108 is positioned below the digital switch 104 with respect tothe input button surface 102. For example, the input button surface 102may receive an actuating force from the user, and may include a rubbermembrane, a cover, etc. The digital switch 104 may include a C plusinner circle switch arrangement, a metal dome sitting on top of the Cplus inner circle components, etc.

In another embodiment, and as shown in FIG. 2, a digital switch may be afirst digital switch 204, and a membrane digital analog switch 200 mayfurther include a second digital switch 212 positioned below the firstdigital switch 204 with respect to the input button surface 202.

In the membrane digital analog switch 200 illustrated in FIG. 2, theanalog switch 206 including the force-sensing resistor 208 is be coupledin series with the second digital switch 212. In this case, the optionalcontroller 210 may be configured to detect a second digital switchactivation signal when the second digital switch 212 is closed.

The controller 210 may measure an initial resistance of theforce-sensing resistor 208 in response to detecting the second digitalswitch activation signal. The controller 210 may set the measuredinitial resistance as a calibration value for measuring an analogforce-sensing resistor signal corresponding to the resistance of theforce-sensing resistor 208 to determine the received input pressure onthe input button surface 202.

For example, the force-sensing resistor 208 may have a non-linearcharacteristic, may have low repeatability, etc. The force-sensingresistor 208 may have an initial high resistance and fall rapidly aspressure is initially increased, then change resistance more slowly asthe pressure continues to increase.

When the force-sensing resistor 208 is connected in series with thesecond digital switch 212 as shown in the example embodiment of FIG. 2,the starting point of user engagement of the force-sensing resistor 208is clear. When the second digital switch 212 closes, an initialresistance may be measured and the remaining resistance slope of theforce-sensing resistor 208 may be calibrated from the measured initialresistance.

The membrane digital analog switches 100 and 200 may be included in anysuitable keypad, user input device, etc. For example, FIGS. 3 and 4illustrated keypads 300 and 400 including the membrane digital analogswitches 100 and 200, respectively.

As shown in FIG. 3, the keypad 300 includes two membrane digital analogswitches 100, each including an input button surface 102. An initialpressure on the input button surface activates the digital switch 104,while further pressure on the input button surface 102 activates theanalog switch by changing the resistance of the force-sensing resistor108.

FIG. 4 illustrates the keypad 400 as including two membrane digitalanalog switches 200, each including an input button surface 202. Aninitial pressure on the input button surface activates the first digitalswitch 204, while further pressure on the input button surface 202activates the analog switch by first contacting the second digitalswitch 212, and then changing the resistance of the force-sensingresistor 208. The force-sensing resistor 208 is connected in series withthe second digital switch 212.

Although FIGS. 3 and 4 illustrate keypads 300 and 400, other embodimentsmay include any suitable membrane switch arrangement, layout, etc. Forexample, the membrane digital analog switches may have a slim profile, asealed outer layer (e.g., for inhibiting dust or water entry), etc. Oneor more flexible layers (e.g., polyester, etc.) may be stacked togetherand allow a user to press down on a top of the flexible layers toactivate a button, etc.

The membrane digital analog switches may include tactile switches,non-tactile switches, etc. For example, FIG. 5 illustrates a tactileswitch 500 that includes an overlay 502 (e.g., an input button surface).An electrically-conductive track 514 is positioned on a circuitsubstrate 516.

A metal dome 518 is positioned between the overlay 502 and theelectrically-conductive track 514. When a user presses down on theoverlay 502, the metal dome 518 collapses to contact theelectrically-conductive track 514. A circuit is closed via the contactbetween the metal dome 518 and the electrically-conductive track 514,which may generate a digital activation signal, etc.

A user may be able to feel the collapsing of the metal dome 518 toprovide tactile feedback, and when a user release pressure the metaldome 518 may pop up back to the original position. A force-sensingresistor may be placed below the metal dome 518, below theelectrically-conductive track 514, below the substrate 516, etc.

A non-tactile switch 600 is illustrated in FIG. 6. The non-tactileswitch 600 includes an overlay 602, and an electrically-conductive track614 positioned on a substrate 616. An electrically-conductive pad 620 ispositioned between the overlay 602 and the electrically-conductive track614. When a user presses down on the overlay 602, theelectrically-conductive pad 620 contacts the electrically-conductivetrack 614. A circuit is closed via the contact between theelectrically-conductive pad 620 and the electrically-conductive track614, which may generate a digital activation signal, etc.

As compared to the tactile switch 500 illustrated in FIG. 5, thenon-tactile switch 600 illustrated in FIG. 6 may not provide tactilefeedback to the user when the switch 600 is closed, because the switch600 does not include a collapsing metal dome, etc. A force-sensingresistor may be placed below the electrically-conductive pad 620, belowthe electrically-conductive track 614, below the substrate 616, etc.

As described herein, the example controllers may include amicroprocessor, microcontroller, integrated circuit, digital signalprocessor, etc., which may include memory. The controllers may beconfigured to perform (e.g., operable to perform, etc.) any of theexample processes described herein using any suitable hardware and/orsoftware implementation. For example, the controllers may executecomputer-executable instructions stored in a memory, may include one ormore logic gates, control circuitry, etc.

According to another example embodiment, a method of operating amembrane digital analog switch including an input button surface, adigital switch and an analog switch is disclosed. The method includesreceiving, at the input button surface, an input pressure from a user.

The method also includes generating, by the digital switch, a digitalswitch activation signal when the received pressure on the input buttonsurface is greater than or equal to a specified digital pressurethreshold, and generating, by the analog switch, an analog switchactivation signal when the received pressure on the input button surfaceis greater than or equal to a specified analog pressure threshold.

The specified analog pressure threshold is greater than the specifieddigital analog pressure threshold, the digital switch activation signalis a binary digital signal, and the analog switch activation signal isvariable and corresponds to an analog sensed value of the receivedpressure on the input button surface.

The method may include implementing one or more analog functions of amachine according to the analog switch activation signal, only after thedigital switch activation signal is generated. In some embodiments, theanalog switch includes a force-sensing resistor, and the analog switchis positioned below the digital switch with respect to the input buttonsurface.

The digital switch may be a first digital switch, with a second digitalswitch positioned below the first digital switch with respect to theinput button surface. The analog switch may include a force-sensingresistor, and the analog switch including the force-sensing resistor maybe coupled in series with the second digital switch.

Example embodiments are provided so that this disclosure will bethorough, and will fully convey the scope to those who are skilled inthe art. Numerous specific details are set forth such as examples ofspecific components, devices, and methods, to provide a thoroughunderstanding of embodiments of the present disclosure. It will beapparent to those skilled in the art that specific details need not beemployed, that example embodiments may be embodied in many differentforms, and that neither should be construed to limit the scope of thedisclosure. In some example embodiments, well-known processes,well-known device structures, and well-known technologies are notdescribed in detail. In addition, advantages and improvements that maybe achieved with one or more exemplary embodiments of the presentdisclosure are provided for purposes of illustration only and do notlimit the scope of the present disclosure, as exemplary embodimentsdisclosed herein may provide all or none of the above mentionedadvantages and improvements and still fall within the scope of thepresent disclosure.

Specific dimensions, specific materials, and/or specific shapesdisclosed herein are example in nature and do not limit the scope of thepresent disclosure. The disclosure herein of particular values andparticular ranges of values for given parameters are not exclusive ofother values and ranges of values that may be useful in one or more ofthe examples disclosed herein. Moreover, it is envisioned that any twoparticular values for a specific parameter stated herein may define theendpoints of a range of values that may be suitable for the givenparameter (i.e., the disclosure of a first value and a second value fora given parameter can be interpreted as disclosing that any valuebetween the first and second values could also be employed for the givenparameter). For example, if Parameter X is exemplified herein to havevalue A and also exemplified to have value Z, it is envisioned thatparameter X may have a range of values from about A to about Z.Similarly, it is envisioned that disclosure of two or more ranges ofvalues for a parameter (whether such ranges are nested, overlapping ordistinct) subsume all possible combination of ranges for the value thatmight be claimed using endpoints of the disclosed ranges. For example,if parameter X is exemplified herein to have values in the range of1-10, or 2-9, or 3-8, it is also envisioned that Parameter X may haveother ranges of values including 1-9, 1-8, 1-3, 1-2, 2-10, 2-8, 2-3,3-10, and 3-9.

The term “about” when applied to values indicates that the calculationor the measurement allows some slight imprecision in the value (withsome approach to exactness in the value; approximately or reasonablyclose to the value; nearly). If, for some reason, the imprecisionprovided by “about” is not otherwise understood in the art with thisordinary meaning, then “about” as used herein indicates at leastvariations that may arise from ordinary methods of measuring or usingsuch parameters. For example, the terms “generally”, “about”, and“substantially” may be used herein to mean within manufacturingtolerances.

The terminology used herein is for the purpose of describing particularexample embodiments only and is not intended to be limiting. Forexample, when permissive phrases, such as “may comprise”, “may include”,and the like, are used herein, at least one embodiment comprises orincludes the feature(s). As used herein, the singular forms “a,” “an,”and “the” may be intended to include the plural forms as well, unlessthe context clearly indicates otherwise. The terms “comprises,”“comprising,” “including,” and “having,” are inclusive and thereforespecify the presence of stated features, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, integers, steps, operations,elements, components, and/or groups thereof. The method steps,processes, and operations described herein are not to be construed asnecessarily requiring their performance in the particular orderdiscussed or illustrated, unless specifically identified as an order ofperformance. It is also to be understood that additional or alternativesteps may be employed.

When an element or layer is referred to as being “on,” “engaged to,”“connected to,” or “coupled to” another element or layer, it may bedirectly on, engaged, connected or coupled to the other element orlayer, or intervening elements or layers may be present. In contrast,when an element is referred to as being “directly on,” “directly engagedto,” “directly connected to,” or “directly coupled to” another elementor layer, there may be no intervening elements or layers present. Otherwords used to describe the relationship between elements should beinterpreted in a like fashion (e.g., “between” versus “directlybetween,” “adjacent” versus “directly adjacent,” etc.). As used herein,the term “and/or” includes any and all combinations of one or more ofthe associated listed items.

Although the terms first, second, third, etc. may be used herein todescribe various elements, components, regions, layers and/or sections,these elements, components, regions, layers and/or sections should notbe limited by these terms. These terms may be only used to distinguishone element, component, region, layer or section from another region,layer or section. Terms such as “first,” “second,” and other numericalterms when used herein do not imply a sequence or order unless clearlyindicated by the context. Thus, a first element, component, region,layer or section discussed below could be termed a second element,component, region, layer or section without departing from the teachingsof the example embodiments.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the disclosure. Individual elements, intended orstated uses, or features of a particular embodiment are generally notlimited to that particular embodiment, but, where applicable, areinterchangeable and can be used in a selected embodiment, even if notspecifically shown or described. The same may also be varied in manyways. Such variations are not to be regarded as a departure from thedisclosure, and all such modifications are intended to be includedwithin the scope of the disclosure.

What is claimed is:
 1. A switch comprising: an input button surfaceadapted to receive an input pressure from a user; a digital switchadapted to generate a digital switch activation signal when the receivedpressure on the input button surface is greater than or equal to aspecified digital pressure threshold; and an analog switch adapted togenerate an analog switch activation signal when the received pressureon the input button surface is greater than or equal to a specifiedanalog pressure threshold; wherein the specified analog pressurethreshold is greater than the specified digital pressure threshold. 2.The switch of claim 1, wherein: the digital switch activation signal isa binary digital signal; and/or the analog switch activation signal isvariable and corresponds to an analog sensed value of the receivedpressure on the input button surface; and/or the digital switch ispositioned below the input button surface.
 3. The switch of claim 1,wherein the analog switch includes a force-sensing resistor.
 4. Theswitch of claim 3, wherein the force-sensing resistor includes anon-linear resistance characteristic where a resistance of theforce-sensing resistor decreases non-linearly as pressure on the inputbutton surface is increased.
 5. The switch of claim 4, furthercomprising a controller configured to measure the analog switchactivation signal, and to determine the received input pressure on theinput button surface according to the measured analog switch activationsignal.
 6. The switch of claim 5, wherein the controller is configuredto determine a change in slope of the analog switch activation signal,and compare the change in slope to the non-linear resistancecharacteristic of the force-sensing resistor to determine the receivedinput pressure on the input button surface.
 7. The switch of claim 3,wherein the analog switch including the force-sensing resistor ispositioned below the digital switch with respect to the input buttonsurface.
 8. The switch of claim 3, wherein: the digital switch is afirst digital switch; the switch further comprises a second digitalswitch positioned below the first digital switch with respect to theinput button surface; and the analog switch including the force-sensingresistor is coupled in series with the second digital switch.
 9. Theswitch of claim 8, further comprising a controller configured to: detecta second digital switch activation signal when the second digital switchis closed; measure an initial resistance of the force-sensing resistorin response to detecting the second digital switch activation signal;and set the measured initial resistance as a calibration value formeasuring an analog force-sensing resistor signal corresponding to theresistance of the force-sensing resistor to determine the received inputpressure on the input button surface.
 10. The switch of claim 1,wherein: the input button surface and the digital switch define atactile switch including a metal dome, the input button surfacecomprises an overlay contacting a first side of the metal dome, and asecond side of the metal dome opposite the first side is positioned tocontact an electrical conductor of the digital switch in response to thereceived pressure on the overlay contacting the first side of the metaldome; or the input button surface and the digital switch define anon-tactile switch including an electrically-conductive pad, the inputbutton surface comprises an overlay contacting a first side of theelectrically-conductive pad, and a second side of theelectrically-conductive pad opposite the first side is positioned tocontact an electrical conductor of the digital switch in response to thereceived pressure on the overlay contacting the first side of theelectrically-conductive pad; or the input button surface and the digitalswitch define a rocker switch.
 11. The switch of claim 1, furthercomprising a controller configured to: determine a positive on step inresponse to receiving the digital switch activation signal; and inresponse to determining the positive on step, to implement one or moreanalog functions according to the received analog switch activationsignal.
 12. The switch of claim 11, wherein the one or more analogfunctions include at least one or more of: controlling a speed or flowrate of a machine; and/or controlling a speed of a crane or a vehicle;and/or controlling a flow rate of a concrete pump or a pressure washer.13. The switch of claim 1, wherein the switch is a membrane digitalanalog switch.
 14. A keypad including at least one switch according toclaim
 1. 15. A keypad comprising one or more switches, each said switchincluding: an input button surface adapted to receive an input pressurefrom a user; a digital switch adapted to generate a digital switchactivation signal when the received pressure on the input button surfaceis greater than or equal to a specified digital pressure threshold; andan analog switch adapted to generate an analog switch activation signalwhen the received pressure on the input button surface is greater thanor equal to a specified analog pressure threshold; wherein the specifiedanalog pressure threshold is greater than the specified digital pressurethreshold.
 16. The keypad of claim 15, wherein: the digital switchactivation signal is a binary digital signal; and/or the analog switchactivation signal is variable and corresponds to an analog sensed valueof the received pressure on the input button surface.
 17. A method ofoperating a switch including an input button surface, a digital switch,and an analog switch, the method comprising: receiving, at the inputbutton surface, an input pressure from a user; generating, by thedigital switch, a digital switch activation signal when the receivedpressure on the input button surface is greater than or equal to aspecified digital pressure threshold; and generating, by the analogswitch, an analog switch activation signal when the received pressure onthe input button surface is greater than or equal to a specified analogpressure threshold; wherein the specified analog pressure threshold isgreater than the specified digital analog pressure threshold.
 18. Themethod of claim 17, wherein: the digital switch activation signal is abinary digital signal; and/or the analog switch activation signal isvariable and corresponds to an analog sensed value of the receivedpressure on the input button surface.
 19. The method of claim 17,further comprising implementing one or more analog functions of amachine according to the analog switch activation signal, only after thedigital switch activation signal is generated.
 20. The method of claim17, wherein: the analog switch includes a force-sensing resistor, andthe analog switch is positioned below the digital switch with respect tothe input button surface; and/or the digital switch is a first digitalswitch, a second digital switch is positioned below the first digitalswitch with respect to the input button surface, and the analog switchis coupled in series with the second digital switch.